1. Field of the Invention
The present invention relates to a liquid crystal display and a method of manufacturing the same and, more particularly, to a vertically aligned liquid crystal display and a method of manufacturing the same.
2. Description of the Related Art
In a vertically aligned liquid crystal display, a liquid crystal having negative dielectric constant anisotropy is vertically aligned using vertical alignment films when no voltage is applied and aligned at a tilt when a voltage is applied. Since liquid crystal molecules are vertically aligned when no voltage is applied, a vertically aligned liquid crystal display has advantages including high quality in displaying black, and capability of displaying at a high contrast, a wide viewing angle, and high response.
For example, methods of regulating the alignment of the liquid crystal of such a vertically aligned liquid crystal display include a pixel configuration as disclosed in JP-A-2004-266560. FIG. 25 is a plan view of a pixel showing a pixel configuration according to the specification. Referring to FIG. 25, a region defined by gate bus lines 14 and drain bus lines 16 is a pixel region, and a pixel electrode 20 is formed in the pixel region, the pixel electrode including three electrode units in the form of rectangles having rounded corners. A storage capacitor bus line 22 is formed in the middle of the pixel substantially in parallel with the gate bus lines 14. A storage capacitor electrode 34 is formed above the storage capacitor bus line 22 with an insulation film (not shown) interposed between them. On an opposite substrate which faces the pixel region with a liquid crystal interposed between them, a point-like alignment regulating structure is formed in a position substantially in the middle of each electrode unit. In such a configuration, as shown in FIG. 26, liquid crystal molecules 76 aligned vertically to the substrates are tilted by distortion of electric fields generated at edges of the electrode units and the alignment regulating structures on the opposite substrate when a voltage is applied, whereby the liquid crystal molecules are aligned in directions from the peripheries of the electrode units toward the centers of the same.
However, since the electrode units themselves of the liquid crystal display in the example are entirely composed of solid patterns as shown in FIG. 27, there will be a large area in which the alignment of liquid crystal molecules can not be controlled with the electrode units when the patterns are large. In particular, since there is no measure for fixing singular points of liquid crystal alignment outside the electrode units, variation occurs in positions where singular points are generated. For this reason, it is difficult to align liquid crystal molecules in directions from the peripheries of the electrode units toward the centers thereof uniformly, and there will be a region having abnormal alignment as illustrated which will appear as granularity in display.
When an external force is applied to the panel of the liquid crystal display by a press with a finger, it is difficult to restore the initial state of singular points which are thus once disturbed.
Further, when edges of the electrode units are close to gate bus lines or drain bus lines, the original liquid crystal alignment is affected by electric fields generated between the edges and the bus lines.
A method of manufacturing color filters disclosed in JP-A-10-177109 includes a first step of forming a light shield layer on a substrate, forming a photosensitive resist layer on the light shield layer, exposing and developing the photosensitive resist layer in a predetermined pattern; etching the exposed light shield layer to form a black matrix constituted by the light shield layer having the predetermined pattern; and curing the photosensitive resist layer on the black matrix to provide a resist layer and a second step of repeating an operation of forming a color layer in a region for forming a layer in a predetermined color in a region of the substrate where the black matrix is not formed and in a region of the resist layer where a columnar spacer is to be formed, a number of times equivalent to the number of colors of color layers to be formed.
However, the gist of the prior document is to form a spacer for maintaining a cell gap by forming color layers on the resist on the black matrix one after another. In the structure disclosed in the specification, since a surface of a common electrode on a CF substrate facing a central part of a pixel electrode unit is at the same height as a surface of the common electrode of the CF substrate facing a non-electrode part at the outer periphery of the electrode unit, there is no measure for fixing singular points of liquid crystal alignment outside the electrode unit, which results in a problem that there is a large area in which the alignment of liquid crystal molecules cannot be controlled.
As thus described, difficulty in controlling singular points increases when the size of an electrode unit is increased. For this reason, an electrode unit is limited to a predetermined size in practice.